Answer:
The birds are oviparous in nature and produces eggs that are hatched later by the parent. the egg hatching require proper heat and protection from the external enemy.
The egg shell is the hard covering of the egg of the bird that is made of the calcium. The egg shell protect the egg from the external environment. The calcium layer for the egg shell formation is obtained by the oseteoclast property of the cells.
Answer:
Lack of oxygen
Explanation:
There are two mechanisms for energy production (glucose breakdown), aerobic and anaerobic. When adequate amounts of oxygen are present, aerobic mechanism is used. However, when there is insufficient oxygen, such as during exercise, the anaerobic mechanism is used.
I think B seems like the answer.
The answer would be D.
HWE states that genotype and allele frequencies in a population remain constant from generation to generation when evolutionary influences are absent(such as gene flow or natural selection).